Hydraulic engine for control devices



Jan. 4 1927. 1,612,818

c'. HowsE HYDRAULIOENGINE FOR CONTROL DEVICES Filed March 2, 1922 v warf/3 5759/1 I ZW A @j Patented Jan. 4, 1927.

l iriasis UNiTED STATESv PATENT OFFICE.

CURTIS L. HOWSE, OF DETROIT, MICHIGAN, ASSIGNOR TOCRAIG DAMPER REGULATOR COMPANY, A CORPORATION OF DELAWARE.

HYDRAULIC ENGINE FOR CONTROL DEVICES.

Application filed March 2, 1922. Seria1..No. 540,652.

My invention has for its general object to provide a novel and improved engine, hydraulically operatable to regulate the position of a part to be controlled by movement of the engine-piston to, and its maintenance in, different positions longitudinally of its cylinder, which will be simple in construction, eicient, powerful and smooth in its functioning', highly sensitive to control of its piston movement, rugged and'| adurable in structure and readily adaptable to diveisified utilization.

For attainment of these and other objects, which will become apparent to those skilled in `the-art from the following description, taken in conjunction .twitli the k'illustrated drawings, my invention consists in the conibinations hereinafter set forth andthe features of construction set forth and claimed.

In various ,situations itis desirable-to regulate the position lof a part of one apparatus vaccordantly withl conditionsv that affect the position of the parts of a condition-responsive apparatus through the intermediacy of an engine which isV controlled by` the condition-responsive part and which, actuated by power derived from some convenient source, forcefully actuates the part to be controlled, VFor onefinstance, it is `desirable to move the stack-damper of a steam boiler-furnace in accordance with pressure conditions existing in the boiler of the furnace, and my invention maybe embodied in form to actuate such a stack-damper acn` cordantly with such Vpressure conditions as thesame are shown by the movements of a pressure-responsive device. In the drawing I illustrate my invention in such an embodi- Vment, for purposes of disclosure of one praclili tical'application thereof but without intent to limit theY invention to such utilization.

In the drawing,Fig. vl'is a diagrammaticr side elevation with f parts broken awayn showing myinvention applied to .damperi'egulation accordantly with steam pressure conditions; Fig. 2is an enlarged view withV parts broken away.; Fig. 3 is a smallrplan` view of the parts'shown in Fig.- 2; and Fig. 4 is a 'detail -of an adjustable crank arrangement. Y y Y i In' the drawing'lO represents-the steam boiler of a furnace 11',- the stack 12 of which contains damper 13 to be niovedaccordantly with'fvariations in v boilerpressurey The damper' regulating engine la, valve-conthis end only of the cylinder is open, as at 7 the port 20, for reception or expulsion of liquid fromfthe source 15. In the specic construction shown weight 19 is adjustable on a .lever 21 which is pivoted as at 22 and which also carries lthe rack segment 23' forA operating a gear wheel 2l on t-he shaft of damper 13, the opposite end of said lever having link connection 25 with the piston rod 26 of the engine. `'Ihe hydraulic pres-- sure supply pipe 27 connects with'the casing of the valve structure 28, the pipe opening to the vertical cylinder 29 for a doubleheaded supply valve 30 at an elevation slightly above that of port 2O so that water pressure may constantly be exerted betweenthe valve heads in any position of the .limited range of axial movement of the valve. In lowered position the valve will open communication between fluid supply pipe 27 and port 20; in mid-position or neutral position it will close the port 20, ensealingthe liquid-receptive end of the cylinder; andin raised positionv it opens communication from kport 20 through. the bottom of valve cylinder 29 to a relief connection 31 piped, say, to a wateredisposal sewer, and preferably have a branch connection 32, to the lower end of thel cylinder of the engine,'so asjto maintain the latter normally underatmospheric pressure and to drain off any liquid that may leak into it; A duct'SS may Aalso lead from this relief connection to the valvefcylinder above the valve, so that the valve will be perfectly balanced.

The conditionfresponsive device 16 that primarily will control the-"movements of' valve' 30 may be of any suitable extensible veniently be utilized.

The slide valve is subjected to dual control from the pressiire-responsive device on the one hand and the engine piston on the other, so that. it may be moved from neutral position to connect port 2() With, alternatively, the source of pressure supply or the relief connection, by the condition-responsive device. and `then may be moved back to neutral position b v lthe piston as the result of the piston travel following: from the introduction or expulsion of liquid due to the first-stated movement of the valve.

In the specific construction shown the valve stem 30 is connected to horizontal lever which has tivo pivotal connections 41 and 42 to links 43 and 44 for respective connection to the piston-controlled part and to the condition-responsive device 16, such lever 40 being preferably adjustably countervveighted as at 45 to load the pressure responsive part. Link 44 may make direct pivotal connection as at 46 with the movable head 38 of the Bourdon spring, and for adjustment it may include a turnbuckle 47. Link 43 is pivoted as at 49 to an adjustable crank pin of a rocking head 50, which is mounted in a 4suitable .ear ofthe bracket 36 and has connected with it an operatinglever 51, the slotted end 52 of Which connects With a pin on the vertical bar 53 carried by and moving with the piston rod, but of course arranged on the exterior of the cylinder 1S. Conveniently the adjustable-throw connection of lever 51 with link 43 may be provided by making the head (Fig. 4) connectible with lever 51 by a non-circular shaft 54. and providing in the head 50 for each of the positions that the head may take with respect to lever 51, a properly positioned hole each a different radial distance from the rotative axis of the head, to receive the crank pin 49. A guide 56 on the upper end of the 'valve-casting may keep the link 43 always in vertical position, for alignment with valve stem 30 on link 44. A

In operation the piston 17 stands normally between its extremes of movement in the cylinder, maintained against rising' under the constant effort of the Weight 19 by the presence of a'liquid body lillingthe cylinder above the piston and po'cketed in the cylinder by the normal closure of port 2O by the lower head of the valve member 30. This condition Will be changed only in response to valve operations initiated by the condition-responsive device 16. Assume boiler pressure to drop: such change should be met by an opening action of the damper tending' to increase the draft, and the engine 14 effects such damper-adjustment. The pressure drop in the boiler permits the pressure gauge 35 to contract, exerting a downward pull on link 44 so that the left end of lever 40, fulcruming on pivot point 41. rises, raising` the valve 30 to open port 2() in communication with the relief passage 31. Tein'ht 19 noiv raises the piston, forcing` liquid out of the space above it, but as the piston rises it carries With it lever-arm 51, turning` crank head 50 and pulling down on link 43, so that the left end of lever 40, now fulcruming on the pivot. point 42, is depressed until Vthe valve is againr neutralizedJ that is to say, positioned so that its loiver head closes the port 20. Of course the raising lof the piston rocks lever 21 to move the damper 13 toivardv open position. On rise of boiler pressure the engine piston will be depressed against the tension of Weight 19, to impart a closing movement to the damper and throttle-down the draft. The vrise* in boiler pressure expands the gauge 35 so that link 47 lifts the right end of lever 40 and depresses the valve 30 until thespace betweenV the valve heads opens connection between pressure supply pipe 27 and theV cylinder. Hydraulic pressure forces dovvn the piston, unt-il the stated link andv crank connections between the piston rod and lever 40 raise the valve to neutral position.

It will be understood that While I have shown details of engine construction in a very simple form having' many advantages, and some of the features of which I may claim` for their specific merits, my invention is not limited thereto in its broader aspects and many departures from the precise mechanism shown may be made Within the spirit of my invention and Within the scope of the appended claims. i'

I claim: i

1. In a device of the character described. a cylinder, a single piston therein loaded to tend to move toward one end of said cylinder, liquid-pressure supply and relief connections for said end of said cylinder, valvemeansnormally closing both of said connections and movable to open eitherthereof alternatively, a pressure-.responsive device having a portion movable under changes of pressure, a valve-.moving lever pivotally connected With the movable portion of said valve, a link connection between said lever and the movable portion of said pressureresponsive device, alink (43) also connected With said valve-moving lever, a crank adjustably and pivotally connected with the other end or" said last-mentioned link to shift the latter bodily with throw variable by said adjustment, and an operating` connection for said crank movable with the piston to turn said crank, said two links providing alternative `fulrra for said lever whereby operation or' said pressure-responsive device, rocking said lever on the other link may open said valve to connect the cylinder with either the pressure or relief connection, and resultant movement of said piston, operating said crank and its connected link will restore the valve to closed position.

2. In a. device of the character described, a cylinder, a pistontherein loaded to tend to move toward one end of said cylinder, hydraulic pressure supply and relierl connections for said Cylinder end, valve-means normally closingboth said connections and movable to open either thereof alternatively, a Bourdon spring` pressure-responsive device, operative connections between said device and Jthe valve means for movingl said valve in either direction, and operative connections including a crank and a link relatively adjustable to vary the effective throw of the crank, arranged between the piston and said valve means for restoring the latter to normal position. A

3. In a device of the character described, a cylinder, a piston therein loaded to tend to move toward one end of said cylinder, hydraulic pressure supply and relief connections for said cylinder end, valve-means normally closing both the connections and movable to open either thereof alternatively, a lever connected to said valve, a pressureresponsive device operatively connected to said lever at one point, a link operatively connected with another point of said lever, a crank member. means to connect said crank member' and link in diferent positions of adjustment to vary the ell'ective throw of the crank, and operative connections between the piston and said crank, substantially as and for the purpose described.

CURTIS L. HOVSE. 

